Liquid level indicator



Aug. 20, 1929. T. M. EYNON LIQUID LEVEL INDICATOR Filed Feb. 28. 1925 INVENTOR:

Patented Aug. 20, 1929.

- UNITED STATES PATENT OFFICE.

LIQUID LEVEL INDICATOR.

Application filed February 88, 1925. Serial No. 12,203.

My invention consists of a novel construction of a liquid level indicator, which is capable of general application, but is especiall adapted for utilization in connection 'wit the instrument board of an automobile to indicate the height of the gasoline level in the gasoline tank, my novel device being devoid of any moving parts, and the indicating device being operated under or subjected to variations of pressure contained within a casing closed at its top and open at its bottom and contained within said gasoline tank, the closed top of said casing communicating through a U tube of a length substantially equal to the height of the tank, with an open ended cup. of lesser diameter and capacity than said casing.

My invention further consists, in conjunction with a device having the above characteristics, of a perforated outer bafile casing surrounding the above mentioned casing and contained'in the gasoline tank, so designed that any splashing of the gasoline, or other liquid being measured, will not affeet the correct and accurate measuring of the liquid and the proper reading of the indicating devices on the instrument board.

It further consists of a novel construction of an .automatic indicating device, operated solely by variations of pressure within the casing contained in the gasoline or other liquid tank, and wherein I dispense entirely with a float in the gasoline chamber and with all mechanical or moving connections intermediate said gasoline chamber and the indicating device, so that there is no liability.

of the apparatus getting out of order, after being installed in .position and owing to its great simplicity and the ab the chassis.

sence of any me chanical connections, it can be readily 1n-' is not affected by the varying positions or inclinations of the gasoline tank durin the progress of the automobile up or own grades, hills, mountains .or the like.

It further consists of other novel features of construction and advantage all as will be hereinafter fully pointed out and set forth in the claims.

For the purpose of illustrating myinvention I have shown in the accompanying drawings forms thereof which are at present preferred by me, since they have been found in practice to give satisfactory and reliable results, although it is to be understood that the various instrumentalities of which my invention consists can be variously arranged and organized and that my invention is not limited to the precise arrangement and organization of these instrumentalities as herein shown and described.

Fig. 1 represents a verticalsectional View of a liquid level indicator embodying my in vention, the tank being shown in section and the baffle cylinder shown in Figs. 3 and 5 has been omitted for the purpose of more clearly illustrating the casing.

Fig. 2 represents a side elevation of the U tube and its adjuncts, showing a modified form of my invention, as applied to tanks of greater vdepths.

Fig. 3 represents a vertical sectional view of the gasoline tank, the bafile casing and its adjuncts.

Fig. 4 represents a section on line 4-4 of Fig. 2. v r

Fig. 5'represents a section on line 5--5 of Fig. 3.

Referring to the drawings I In carrying out my invention I position on. the base 1 of the gasoline or other tank 2, a-casing 3, which is open at its bottom 4, and closed at its top, and provided with thefeet 5, which may rest directly upon the bottom 1 as seen in.Fig. 1 or said casing 3 may be contained within the perforated outer bafile casingfi, which is closed at its bottom and open at its top and provided with the perforations 27 as seen in Fig. 3.

p The lowermost row of small holes 27, while admitting the liquid to the casing 3, are a suflicient distance above the open-bottom 4 of the'casing 3, to maintain a liquid seal about said openin 4 at all times regardless -of the amount 0 liquid in the tank, by

retaining a quantity of the liquid in the ion bottom of the outer baflle casing 6, to the level of the lowermost row of holes 27. 8 designates the top of the casing 3 from -which extends the pipe 9, through the tanks as used on automobiles, where the reading of the scale is confined to a vertical height of from two to three inches, suitable for the instrument board of the automobile. In the construction seen in Fi. s. 2 and 4 which is particularly adapted or'tanks .of

greater depth, such as storage tanks, and

in which a greater scale length is required for accuracy, due to the greater depth to be measured the pipe 9 is bent at 18 and connected to the transparent vertical member 19 opposite to which is the scale 20. The

vertical member 19 connects with the bend 21 and the bend 21 is continued upwardly to form the branch 22 upon the upper .end

of which is the enlarged tubular or cup shaped member 23, corresponding to the member 16. By this modification of my invention it is possible to have, a scale length equal to about three quarters of the diameter or height of the tank, thereby obtaining greater accuracy in the measurement. When the gasoline level is at about the point'24l, the'level of the liquid in the casing 3 .will be as indicated at 25, and the level of the liquid in the cup 16 will be as indicated at 26.

The operation of my novel liquid levelindicator is as follows :-A liquid indicating medium, preferabl a light non-volatile oil, is placed into the limbs 13 and 15 of the U tube, to a level of the zero on the scale 17. The cylindrical casing 3 is then immersed into the gasoline or other liquid, or,

as it would be carried out normally, the tank 2 is filled with gasoline in the usual way, While the casing cylinder 3 is in position. The cylinder 3, as well as the communicating tubing being filled with air, the gasoline risesin the casing? and forces the air out of the cylinder 3 into the communicating tubing 9 and 12, thereby forcing the level of the indicating medium in the glass 16, upwardly. By properl selecting the relative diameters of the cy indrical casing 3, and the auge glass 16, the indicating medium in t e gauge glass may be made to rise f any suitable amount for a certain risein the level of the gasoline in the tank. These casing 3 and the glass 16', and since such diameters are *fixedin any particular case,

the rise in the level of the indicating medium Will indicate accurately at all times the exact level of the liquid in the tank, regardless of the temperature ofthe. tank, the liquid contained therein, or the temperature of the communicating tubing and the air contained therein. Thus on raising the temperature of the gasoline or the communicating tubing,

the surface 25 of the gasoline in the cylinder casing 3 is merely lowered, without however affecting the reading on the scale 17, since the level 24 of the gasoline in the tank is not appreciably affected by any expansion of the air in the communicating tubing.

The bafile cylinder or casing 6 shown in Figs. 3 and 5, serves two purposes. It first acts as a battle wall surroundingthe opening 4 at the bottom of the cylindrical casing 3, so as to, prevent, any momentary variations'in the level of the gasoline in the tank, or any-"splashing of the gasoline, from materially affecting the level of the liquid indicating nedium in the glass 16; that is preventing any fluctuation in the reading of the gauge due to such splashing. This ba-file Wall tends to give, what might be called, an average reading ofthe. level of the gasoline, instead of a fluctuating reading. The second purpose of the outer baflie cylinder or casing 6, is to retain a certain amount of liquid, gasoline, around the bottom opening 4 of the cylindrical casin 3 at all times, even though the gasoline tan may be emptied completely-as. might happen occasional- I ly in practice. Thus the lower openings or apertures 27 which extend around the cylindrical surface of said bafile wall, are a certain distance above the level of the opening 4, thereby retaining a liquid seal around said lower opening 4:, at all times.

The condition that has made it impossible in the past, to use gages, where an exact visual reading of the quantity of liquid in the tank is at all times demanded, when air or liquids are used to transmit the pressure from the tank to a remote distance where the gage or scale is located; isthe expansion and contraction of the transmitting medium by the constantly changing temperature, both of the instrument itself,-and of all the pipes used in transmitting the pressure tothe instrument.

I have overcome the effects of expansion and contraction, due to the changes in temperature, by a very scientific, practical and in the statement of the invention and the above description, and while I have, in the resent instance, shown and-described a preerred embodiment thereof which will give in practice satisfactory and reliable results, it is to be understood that such embodiment is susceptible of modification in various particulars without departing from the spirit or scope of the invention or sacrificing any of its advantages.

Having thus described my invention,- what I- claim as new and desire to secure by Letters Patent is x 1. Liquid level measuring apparatus of the character stated, comprising a receptacle containing liquid to-be measured, a casing having a closed-top and an open bottom arranged in said liquid, a stufling box for said receptacle, a pipe extended from the top of said casing through said stufiing box and having its upper en bent downwardly and .then upwardly to form a U tube, part of which is transparent, an elongated open top container carried by said U tube which container is of lesser diameter and capacity than said casing, and aperforated baflle cylinder surrounding said casing which baflle cylinder is closed at its bottom and open at its top, said baflie cylinder being seated upon the receptacle bottom with the open bottom of said cylindrical casing spaced from the baflle cylinder bottom.

2. Liquid level measuring apparatus of the character stated comprising a receptacle containing liquid to be measured, a stufling box for said receptacle, an inner, cyl1ndrical casing having an open bottom, said casing being arranged in the liquid to be measured, feet for supporting said cylindrical casing, a removable closure for the. top

of said casing, a pipe extended from said removable closure through said stufiing' box and having its u per end bent to form a U tube, an elon ate tainer carried by the upper end of said U tube, part of which U tube is transparent, said container being of lesser diameter and capacity than said innercylindrical casing,

'50 open top cylindrical conan outer perforated bafile cylinder open at w its top and closed at its bottom surrounding said inner casing, with the feet of the inner between the closed top of the inner casin casing resting upon the bottom of said bafile andthe liquid in the lower portion thereot,

said open top container and U tube being provided with a'liquid, and a scale for indicating the variations in height of said liquid.

THOMAS M. EYNON. 

